A transmitter in a mobile communication system may have an error correction coder to perform error correction coding (e.g. convolutional coding) of data to be transmitted. A receiver in such a system may contain a decoder (e.g. Viterbi decoder) to decode the error correction coded data and to recover the original data. There are many well known coding and decoding methodologies, including turbo coding add decoding. Turbo decoders, among others, may utilize a two phase process for decoding all encoded data block having N elements, a forward phase and a backward phase. Each phase may be calculated recursively, the forward phase generating a forward state matrix and the backward phase generating a backward state mat. An element from the forward state matrix, αn, may be calculated from a previously calculated element, αn−1, and an element for the backward state matrix, βn, may be calculated from a numerically successive element βn+1. The posteriori probability estimation related to element n is based on combining the information gained from αn, and βn+1. Turbo decoders and their decoding methodology are well known. Any formulas or algorithms for calculating a forward matrix, a reverse matrix, and We decoder output, currently known or to be devised in the fixtures are applicable to the present invention. FIG. 1 is a diagram illustrating forward and backward iterative calculations being performed on an encoded block of data according to the prior art.
It will be appreciated that for simplicity and clarity of illustration elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.